We propose to study morphogenesis and cell division using the bacterium Myxococcus xanthus as a model system. Our approach is to use biochemical techniques to probe: (a) the role of 3':5' cyclic AMP metabolism in development. The cAMP-phosphodiesterase will be purified and characterized. We also plan to purify adenyl cyclase and the cAMP receptor protein(s). The levels of cAMP, adenyl cyclase and cAMP phosphodiesterase production will be studied during the developmental sequence; (b) transcriptional and translational regulation of development. The RNA polymerase from M. xanthus will be purified and characterized. Differences between vegetative and sporulation specific enzymes or factors will be investigated. Translational regulation will be investigated using spectinomycin resistant mutants and bacteriophage restriction as probes; (c) chromosome replication and cell division during development. The size of the Myxococcus chromosome will be investigated by autoradiography of intact chromosomes, viscoelastic properties, and re-association kinetics. The direction(s) of chromosome replication will be determined. The relationship of DNA synthesis to cell division and development will be studied using inhibitors of DNA synthesis, cell division mutants, and chemical analyses of spores.